Title

Author(s)

Document Type

Journal Article

Date of this Version

4-2014

Publication Source

PS: Political Science & Politics

Volume

47

Issue

2

Start Page

427

Last Page

431

DOI

10.1017/S1049096514000341

Abstract

We review the performance of the PollyVote, which combined forecasts from polls, prediction markets, experts’ judgment, political economy models, and index models to predict the two-party popular vote in the 2012 US presidential election. Throughout the election year the PollyVote provided highly accurate forecasts, outperforming each of its component methods, as well as the forecasts from FiveThirtyEight.com. Gains in accuracy were particularly large early in the campaign, when uncertainty about the election outcome is typically high. The results confirm prior research showing that combining is one of the most effective approaches to generating accurate forecasts.